溶液中の二核金属複合体の振動緩和とシステム間交差
Renske M van der Veen1, Andrea Cannizzo, Frank van Mourik
1Ecole Polytechnique Fédérale de Lausanne, Laboratory of Ultrafast Spectroscopy, ISIC, 1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|December 18, 2010
まとめ
[Pt2(P2O5H2) ]4-複合体における超高速の振動のリラックスと波束の振動が研究されました. 溶媒の相互作用は,振動による冷却とシステム間交差速度の上昇に大きく影響する.
科学分野:
- フォトケミストリー フォトケミストリー
- 物理化学 物理化学
- スペクトル顕微鏡検査です.
背景:
- 二核プラチナ複合体は,興味深い光物理的性質を示しています.
- 超高速ダイナミクスを理解することは,新しい材料の設計に不可欠です.
研究 の 目的:
- [Pt2(P2O5H2)4]4-.における超高速振動電子リラクゼーションを研究する.
- 興奮状態ダイナミクスにおける溶媒の役割を明らかにする.
- 振動のリラックス,波のパケットの振動,システム間の交差を特徴付けます.
主な方法:
- フェムト秒ポリクロマティック光アップ変換スペクトロスコーピー.
- フェムト秒 ブロードバンド トランジエント 吸収 (TA) スペクトロスコーピー.
- 溶剤依存研究.溶剤依存研究.
主要な成果:
- 観測されたPt-Ptストレッチ振動波パケットの振動 (224 fs周期) を (1) A. 2 u. 状態で観測した.
- 振動のリラックスとシステム間交差 (ISC) 時間は,溶媒への強い依存を示しています.
- 振動による冷却のためのPt溶媒による直接的なエネルギー分散が確立されています.
- ISCの原動力として,スピン-ビブロニックカップリングと対称性破裂を特定した.
結論:
- [Pt2(P2O5H2)4]4-は,光学的なブロッホの記述から逸脱する調和振動器の振る舞いを示しています.
- Pt-溶媒による直接的なエネルギー分散は,振動による冷却を容易にする.
- 分子構造,エネルギー,対称性は,強いスピン軌道結合にもかかわらず,ISC率を制御します.
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